KR20140011288A - Lubricant compositions for direct injection engines - Google Patents

Abstract

The present invention relates to a lubricant additive for reducing inhalation valve deposits in an SIDI engine, a crankcase lubricant composition, and a method for the lubrication. The lubricant additive comprises an aromatic group compound having a boiling point under the standard atmosphere of 190-270°C. When 0.1-5.0 wt% of the aromatic group compound is added to the total weight of the lubricant composition containing the additive, the reduction of deposits is effective.

Description

Lubrication composition for direct injection engines {LUBRICANT COMPOSITIONS FOR DIRECT INJECTION ENGINES}

The present disclosure relates to lubricating compositions, in particular additives, for improving reducing the amount of intake valve deposits formed adjacent the intake valves of a direct injection spark ignition (SIDI) engine.

Direct injection spark ignition (DIDI) engines have been investigated for the benefits of fuel economy and reduced CO ₂ emissions for over 90 years. Technical challenges included fuel management control, exhaust emission control, injector fouling and engine deposits. Asian and European manufacturers are both engaged in driving SIDI engine technology. However, the SIDI engine does not have a port fuel injector for cleaning and removing deposits on the intake valve. Therefore, there is no effective removal method for the intake valve of the SIDI engine, and deposits tend to accumulate over time. Intake valve deposits eventually accumulate to the point where the valve keeps open, causing loss of engine compression or catastrophic failure in the event that the piston crown strikes the open valve.

Deposits can accumulate on the intake valves of the SIDI engine, causing the vehicle to shut down around 35,000 miles and the valves to be cleaned by mechanical means. Until now, engine deposits were believed to occur first in the fuel, so various fuel additives have been used in attempts to reduce the formation of engine deposits. However, it is now surprisingly found that the intake valve deposits of the SIDI engine first arise from the lubricant used in the engine. Oil vapor from the lubricating composition is believed to enter the intake valve port through a positive crankcase ventilation (PCV) circuit and the vapor condenses at the valve to form deposits. Accordingly, what is needed is a lubricating composition and method for reducing the amount of deposits formed in the intake valve of a SIDI engine.

In view of the above, embodiments of the present disclosure provide lubricating additives, crankcase lubricating compositions and methods for reducing intake valve deposits in direct injection spark ignition (SIDI) engines. Lubricating additives include aromatic compounds having boiling points under standard atmospheric conditions of about 190 to about 270 ° C. Aromatic compounds are effective at reducing intake valve deposits in SIDI engines when used in amounts ranging from about 0.1 to about 5.0 weight percent based on the total weight of the lubricating composition containing the additive.

The use of aromatic additives having a boiling point in the range of about 190 to 270 ° C. in engine lubricating compositions is contrary to the common belief that there is a tendency to avoid the use of volatile organic compounds in such lubricating compositions. In addition, the lubricating additives described herein were not expected to be more effective than fuel additives in reducing intake valve deposits in SIDI engines.

An unexpected advantage of the use of the aromatic additives of the disclosed embodiments is that SIDI engines containing aromatic additives can be used in automobiles driven without additives without loss of engine efficiency or performance due to limited air flow at the intake valve ports of the engine. Can be driven for more than twice the mileage. Other benefits and advantages may be apparent from the following detailed description and the accompanying drawings.

Additional details and advantages of the disclosure will be set forth in part in the description which follows, and / or may be learned by practice of the disclosure in conjunction with the accompanying drawings as follows:
1 is a photograph of an intake valve and valve port from the air inlet side of a valve port for a vehicle with a SIDI engine run for 35,184 miles without aromatic additives as described herein.
FIG. 2 is a close-up picture of deposits on the valve stem of the intake valve of FIG. 1. FIG.
3 is a photograph of a representative intake valve and valve port for a motor vehicle having a SIDI engine run for 80,912 miles with aromatic additives in accordance with embodiments of the present disclosure.
4 is a close-up photograph of deposits on the valve stem of the intake valve of FIG. 3.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and do not limit the disclosure as claimed. The details and advantages of the disclosure may be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.

The present disclosure will now be described in more limited aspects of its embodiments, including various examples of formulations and uses of the present disclosure. It is to be understood that such embodiments are presented solely for the purpose of illustrating the invention and are not to be considered limiting of its scope.

With respect to exemplary embodiments, the definitions of the following terms are provided to clarify the meaning of the specific terms used herein.

As used herein, the terms “oil composition”, “lubricating composition”, “lubricating oil composition”, “lubricating oil”, “lubricating composition”, “lubricating composition”, “fully formulated lubricating composition” and “lubricating” Is considered a synonymous, fully compatible term that refers to a final lubricating product comprising a major amount of base oil + an additional amount of an additive composition.

As used herein, the terms "additive package", "additive concentrate" and "additive composition" are considered to be synonymous, fully compatible terms that refer to portions of the lubricating composition except the main amount of the base oil stock mixture.

As used herein, the term "hydrocarbyl substituent" or "hydrocarbyl group" is used in its conventional meaning well known to those skilled in the art. Specifically, it represents a group having carbon atoms attached directly to the rest of the molecule and predominantly having hydrocarbon properties. Examples of hydrocarbyl groups include the following:

(1) hydrocarbon substituents, ie aliphatic (eg, alkyl or alkenyl), alicyclic (eg, cycloalkyl, cycloalkenyl) substituents, and aromatic-, aliphatic- and alicyclic-substituted aromatic substituents, And cyclic substituents in which the ring is completed through another portion of the molecule (eg, two substituents together form an alicyclic radical);

(2) substituted hydrocarbon substituents, ie substituents containing a non-hydrocarbon group that do not change the dominant hydrocarbon substituent in the context of the present application (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto , Nitro, nitroso, amino, alkylamine and sulfoxy);

(3) hetero-substituents, ie, substituents which, in the context of the present application, predominantly have hydrocarbon properties and otherwise contain other than carbon in a ring or chain consisting of carbon atoms. Heteroatoms include sulfur, oxygen, nitrogen and include substituents such as pyridyl, furyl, thienyl and imidazolyl. Generally, up to two, for example up to one non-hydrocarbon substituent will be present every 10 carbon atoms in the hydrocarbyl group; Typically, the hydrocarbyl group will be free of non-hydrocarbon substituents.

As used herein, the term "% by weight" refers to the percentage of the stated component representatives by weight of the total composition unless otherwise indicated.

The term "soluble" or "dispersible", as used herein, may indicate, but not necessarily that the compound or additive may be soluble, soluble, or suspended in the oil in all proportions. However, the term means, for example, that they are soluble or stably dispersible in the oil to an extent sufficient to have their intended effect in the environment in which the oil is used. In addition, further incorporation of other additives may also permit incorporation of high levels of certain additives, if desired.

The lubricating oils, engine lubricating oils and / or crankcase lubricating oils of the present disclosure may be formulated by addition of one or more additives to the appropriate base oil formulation as described in detail below. The additive can be combined with the base oil in the form of an additive package (or concentrate), can be combined independently with the base oil, or alternatively can be added to the lubricating composition of the engine as a "promoting" additive. As used herein, an “promoting” additive is an additive added to a fully formulated lubricating composition that supplements or increases the amount of the additive component in the lubricating composition, in addition to the usual amount of components typically present in the fully formulated lubricating composition. Is the amount. Fully formulated lubricants, engine lubricants and / or crankcase lubricants may exhibit improved performance characteristics, based on the additives added and their respective proportions.

The engine or crankcase lubricating composition described herein is used in automobiles comprising spark ignition engines, in particular direct injection spark ignition engines. The engine can be used for private and light truck applications and includes, without limitation, gasoline, alcohol-containing fuel, compressed natural gas, gas-to-liquid fuel, biofuel, flex-fuel, mixtures thereof, and the like. Can be operated on fuel. The present disclosure may describe engine lubricants that meet or exceed the proposed ILSAC GF-5 lubricant standard, such as lubricants suitable for use as private crankcase lubricants. Conventional GF-5 lubricating compositions include detergents, dispersants, friction modifiers, antioxidants, rust inhibitors, viscosity index enhancers, emulsifiers, deemulsifiers, corrosion inhibitors, antiwear agents, metal dihydrocarbyl dithiophosphates, ashless amine phosphates It may include one or more additive components selected from salts, antifoams and pour point depressants. According to embodiments of the present disclosure, the lubricating composition also includes an aromatic compound in an amount effective to reduce intake valve deposits in the SIDI engine.

Aromatic additives

According to embodiments of the present disclosure, a relatively volatile aromatic additive is combined with a fully formulated lubricating composition having a boiling point of from about 190 to about 270 ° C. under standard atmospheric conditions, wherein the aromatic compound is a total of lubricating composition containing the additive. It is effective to reduce intake valve deposits in SIDI engines when used in amounts ranging from about 0.1 to about 5.0 weight percent by weight.

Aromatic additive compounds that may be used include compounds of the formula wherein the boiling point ranges from about 190 to about 270 ° C. under standard atmospheric conditions:

[Wherein, R ¹ , R ² and R ³ are each a hydrogen and a hydrocarbyl group having 1 to 6 carbon atoms, provided that at least one of R ¹ , R ² and R ³ is a hydrocarbyl group having 1 to 6 carbon atoms]. Standard atmospheric conditions are room temperature and 1 atmospheric pressure.

Thus, suitable aromatic compounds that can be used to reduce valve deposits in SIDI engines include, without limitation, 2,6-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, 2-tert- Butyl-6-methylphenol, 2-tert-butylphenol, 4-tert-butylphenol, o-cresol, m-cresol, p-cresol and mixtures of two or more of the above. Of these, particularly suitable compounds include hindered phenolic compounds having a boiling point in the range of about 190 to about 270 ° C, for example about 220 to about 265 ° C. Examples of such compounds are 2,6-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-6-methylphenol, 2-tert-butylphenol and 4 -tert-butylphenol.

In comparison to conventional phenolic compounds used in lubricating compositions, the compounds described herein are relatively more volatile than the aromatic compounds commonly used in lubricating compositions. Without being limited by theoretical considerations, the aromatic compounds described herein more easily vaporize and enter the intake air manifold of the SIDI engine along with oil mist and steam in the engine's PCV circuit. While oil mist and vapor containing entrained aromatics are condensed on the intake valve stem and tulip, aromatic compounds can prevent the oil from mist and steam to polymerize, so that the oil is naturally vaporized and consumed in the combustion process Allow plenty of time to get there.

The amount of aromatic additive compound in the lubricating composition is preferably an amount sufficient to maintain the performance and / or fuel savings of the SIDI engine for engine runs greater than about 35,000 miles. Thus, the amount of aromatic additive that can be used in the lubricating composition fully formulated for the SIDI engine can range from about 0.1 to about 5.0 weight percent based on the total weight of the lubricating composition containing the additive. Particularly suitable amounts of additives may range from about 0.5 to about 2.0 weight percent based on the total weight of the lubricating composition containing the additive.

The aromatic additive may initially be present in a fully formulated lubricating composition or may be added to the crankcase or lubricating composition of an engine containing the fully formulated lubricating composition. In another embodiment, the aromatic additive may be added to the crankcase of the engine after the engine has been run for a predetermined number of miles to reduce the amount of deposits formed at the intake valves of the engine.

Base oil

Suitable base oils for use in the formulation of the engine lubricating composition can be selected from any of suitable synthetic or mineral oils or mixtures thereof. Mineral oils include mineral oils such as animal oils and vegetable oils (eg castor oil, lard oil) as well as mineral lubricating oils such as liquid petroleum oils and solvent treated or acid-treated paraffinic, naphthenic or mixed paraffinic-naphthenic type minerals. Lubricating oil. Oils derived from coal or shale may also be suitable. The base oil may typically have a viscosity of about 2 to about 15 cSt or, as an additional example, about 2 to about 10 cSt at 100 ° C. In addition, oils derived from gas-to-liquid processes are also suitable.

Suitable synthetic base oils may include alkyl esters of dicarboxylic acids, polyglycols and alcohols, poly-alpha-olefins, including polybutenes, alkylbenzenes, organic esters of phosphoric acid and polysilicon oils. Synthetic oils include hydrocarbon oils such as polymerized and interpolymerized olefins (e.g., polybutylene, polypropylene, propylene isobutylene copolymers, etc.); Poly (1-hexene), poly (1-octene), poly (1-decene) and the like and mixtures thereof; Alkylbenzenes (e.g., dodecylbenzene, tetradecylbenzene, di-nonylbenzene, di- (2-ethylhexyl) benzene and the like); Polyphenyls (e.g., biphenyl, terphenyl, alkylated polyphenyls and the like); Alkylated diphenyl ether and alkylated diphenyl sulfide and derivatives, analogs and homologs thereof, and the like.

Alkylene oxide polymers and interpolymers and derivatives thereof in which terminal hydroxyl groups are modified by esterification, etherification and the like constitute another class of known synthetic oils that can be used. The oil may be an oil prepared through polymerization of ethylene oxide or propylene oxide, alkyl and aryl ethers of such polyoxyalkylene polymers (e.g., methyl-polyisopropylene glycol ethers having an average molecular weight of about 1000, Diphenyl ether of polyethylene glycol having a molecular weight of 1000, diethyl ether of polypropylene glycol having a molecular weight of about 1000 to 1500, etc.) or mono- and polycarboxylic acid esters thereof, such as acetic acid esters, mixed C ₃ - C ₈ fatty acid esters or C ₁₃ oxo-acid diesters of tetraethylene glycol.

Another class of synthetic oils that may be used are dicarboxylic acids (eg, phthalic acid, succinic acid, alkyl succinic acid, alkenyl succinic acid, maleic acid, azelaic acid, suberic acid, sebacic acid, fumaric acid, adipic acid, linoleic acid). Dimers, malonic acid, alkyl malonic acid, alkenyl malonic acid, and the like and various alcohols (e.g., butyl alcohol, hexyl, alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycol monoether, Propylene glycol, and the like). Specific examples of such esters include diethyl adipate, di (2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, Didecyl phthalate, diecosyl sebacate, 2-ethylhexyl diester of linoleic acid dimer, complex ester formed by reacting 1 mole of sebacic acid with 2 moles of tetraethylene glycol and 2 moles of 2-ethylhexanoic acid; do.

Esters useful as synthetic oils also include those made from C ₅ to C ₁₂ monocarboxylic acids and polyols and polyol ethers such as neopentyl glycol, trimethylol propane, pentaerythritol, dipentaerythritol, tripentaerythritol and the like.

Thus, the base oil that can be used to prepare an engine lubricating composition as described herein can be selected from any of the base oils of Group I-V specified in the American Petroleum Institute (API) Base Oil Compatible Guidelines. The base oil group is as follows:

The base oil may contain a minor or major amount of poly-alpha-olefin (PAO). Typically, poly-alpha-olefins are derived from monomers having from about 4 to about 30, or from about 4 to about 20, or from about 6 to about 16 carbon atoms. Examples of useful PAOs include those derived from octene, decene, mixtures thereof, and the like. The PAO may have a viscosity at 100 DEG C of from about 2 to about 15, from about 3 to about 12, or from about 4 to about 8 cSt. Examples of PAO include poly-alpha-olefins of 4 cSt at 100 DEG C, poly-alpha-olefins of 6 cSt at 100 DEG C and mixtures thereof. Mixtures of mineral oils and the poly-alpha-olefins may be used.

The base oil may be an oil derived from a Fischer-Tropsch synthesized hydrocarbon. Fischer-Tropsch synthesized hydrocarbons are prepared from synthesis gas containing H ₂ and CO using a Fischer-Tropsch catalyst. The hydrocarbons typically require further processing to be useful as a base oil. For example, hydrocarbons can be hydroisomerized using the methods disclosed in U.S. Patent No. 6,103,099 or 6,180,575; Hydrogenolysis and hydrogenation isomerization using the methods disclosed in U.S. Patent No. 4,943,672 or 6,096,940; Deoxidized using the method disclosed in U.S. Patent No. 5,882,505; U.S. Patent No. 6,013,171; 6,080,301; Or 6,165, 949, which is incorporated herein by reference in its entirety.

Crude, refined and refined oils (and mixtures of two or more thereof), minerals or synthetics of the type disclosed above herein, can be used in the base oil. Crude oil is obtained directly from mineral or synthetic sources without further purification. For example, the shale oil obtained directly from the retorting operation, the petroleum oil obtained directly from the primary distillation or the ester oil obtained directly from the esterification process and used without further treatment will be crude oil. Refined oils are similar to crude oils except that they are further processed in one or more purification steps to improve one or more properties. Many of the above purification techniques, such as solvent extraction, secondary distillation, acid or base extraction, filtration, percolation, and the like, are known to those skilled in the art. Refined oils are obtained by methods similar to those used to obtain refined oils applied to refined oils already in use in the field. The rerefined oils are also known as regenerated or reprocessed oils and are often further processed by techniques relating to the removal of already used additives, contaminants and oil degradation products.

Base oils can be combined with the additive compositions disclosed in embodiments herein to provide engine lubricating compositions suitable for crankcases of engines. Thus, the base oil may be present in the engine lubricating composition in an amount ranging from about 50% to about 95% by weight based on the total weight of the lubricating composition.

Dispersant

Dispersants contained in fully formulated lubricating compositions according to the present disclosure may include, but are not limited to, oil soluble polymeric hydrocarbon backbones having functional groups capable of binding to the particles to be dispersed. Dispersants typically include amine, alcohol, amide or ester polar moieties often attached to the polymer backbone via a crosslinking group. Dispersants include Mannich dispersants as described in US Pat. Nos. 3,697,574 and 3,736,357; Ashless succinimide dispersants described in US Pat. Nos. 4,234,435 and 4,636,322; Amine dispersants described in US Pat. Nos. 3,219,666, 3,565,804 and 5,633,326; Koch dispersants described in US Pat. Nos. 5,936,041, 5,643,859, and 5,627,259; And US Patent No. 5,851,965; 5,853,434; And polyalkylene succinimide dispersants described in 5,792,729.

Suitable dispersants that may be used in the fully formulated lubricating composition may include the reaction product of A) hydrocarbyl-carboxylic acid or anhydride or hydrocarbyl-substituted Mannich base and B) polyamines containing at least two nitrogen atoms. Can be. The hydrocarbyl portion of the hydrocarbyl-carboxylic acid or anhydride of component A can be derived from a butene polymer, for example a polymer of isobutylene. Polyisobutenes suitable for use herein include those formed from polyisobutylene or highly reactive polyisobutylene having a terminal vinylidene content of at least about 60%, such as from about 70% to about 90% and higher. Suitable polyisobutenes may include those prepared using BF ₃ catalysts. The number average molecular weight of the polyalkenyl substituent may vary over a wide range of about 100 to about 5000, such as about 500 to about 5000, as measured by GPC described above.

The carboxylic acids and anhydrides of component A are carboxylic reactants other than maleic anhydride, such as maleic acid, fumaric acid, malic acid, tartaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, mesaconic acid, ethylmale Acid anhydride, dimethylmaleic anhydride, ethylmaleic acid, dimethylmaleic acid, hexylmaleic acid, and the like, and corresponding acid halides and lower aliphatic esters. The molar ratio of maleic anhydride to hydrocarbyl moiety in the reaction mixture used to prepare component A can vary widely. Thus, the molar ratio can vary from about 5: 1 to about 1: 5, for example about 3: 1 to about 1: 3, and as further examples maleic anhydride may be stoichiometric to force the reaction to complete. It can be used in excess. Unreacted maleic anhydride can be removed by vacuum distillation.

Any of many polyamines can be used as component B in the preparation of functionalized dispersants. Non-limiting examples Polyamines include aminoguanidine bicarbonate (AGBC), diethylene triamine (DETA), triethylene tetraamine (TETA), tetraethylene pentamine (TEPA), pentaethylene hexamine (PEHA) and heavy polyamines It may include. Heavy polyamines are polyalkylenepolyamines with small amounts of lower polyamine oligomers such as TEPA and PEHA (mainly oligomers have at least 7 nitrogen atoms per molecule, at least 2 primary amines, and are more concentrated branched than conventional polyamine mixtures). It may include a mixture of. Additional non-limiting polyamines that can be used to prepare hydrocarbyl-substituted succinimide dispersants are disclosed in US Pat. No. 6,548,458, the disclosure of which is incorporated herein by reference in its entirety. In embodiments of the present disclosure, the polyamine may be selected from tetraethylene pentamine (TEPA).

The fully formulated lubricating composition may contain from about 0.5% to about 10.0% by weight of the dispersant described above, based on the total weight of the lubricating composition. Typical dispersants may range from about 2% to about 5% by weight based on the total weight of the lubricating composition.

Metal-containing detergents

Metal detergents that can be used with the dispersion reaction products described above generally include polar heads with long hydrophobic tails in which the polar head comprises a metal salt of an acidic organic compound. Salts may contain substantial stoichiometric amounts of metal, in which case they are generally described as normal or natural salts and have a total base number or TBN (measured by ASTM D2896) of about 0 to less than about 150 Will have. Large amounts of metal bases can be included by reacting an acidic gas, such as carbon dioxide, with an excess of a metal compound, such as an oxide or hydroxide. The resulting overbased detergent comprises a micelle of neutralizing detergent surrounding the core of an inorganic metal base (eg hydrated carbonate). The overbased detergent may have a TBN of about 150 or more, such as about 150 to about 450 or more.

Detergents that may be suitable for use in embodiments of the invention include oil-soluble overbased, low base and neutral sulfonates, phenates, sulfide phenates and metals, especially alkali or alkaline earth metals, such as sodium, potassium, lithium, calcium And salicylates of magnesium. More than one metal may be present, for example calcium and magnesium. Calcium and / or mixtures of magnesium and sodium may also be suitable. Suitable metal detergents include calcium overbased calcium or magnesium sulfonate with a TNB of 150 to 450 TBN, calcium overbased calcium or magnesium phenate or sulfide with TBN of 150 to 300, and calcium overbased with TBN of 130 to 350 Or magnesium salicylate. Mixtures of such salts may also be used.

The metal-containing detergent may be present in the lubricating composition in an amount of about 0.5% to about 5% by weight. As a further example, the metal-containing detergent may be present in an amount from about 1.0% to about 3.0% by weight. The metal-containing detergent may be present in the lubricating composition in an amount sufficient to provide about 500 to about 5000 ppm alkali and / or alkaline earth metal to the lubricating composition based on the total weight of the lubricating composition. As a further example, the metal-containing detergent may be present in the lubricating composition in an amount sufficient to provide about 1000 to about 3000 ppm alkali and / or alkaline earth metal.

Phosphorus-based Anti-abrasive

Phosphorous-based antiwear agents may be used and may include, but are not limited to, metal dihydrocarbyl dithiophosphate compounds, such as zinc dihydrocarbyl dithiophosphate compounds. Suitable metal dihydrocarbyl dithiophosphates may include dihydrocarbyl dithiophosphate metal salts, wherein the metal is an alkali or alkaline earth metal, or aluminum, lead, tin, molybdenum, manganese, nickel, copper or It may be zinc.

The dihydrocarbyl dithiophosphate metal salt is generally formed by first reacting at least one alcohol or phenol with P ₂ S ₅ to form dihydrocarbyl dithiophosphoric acid (DDPA), and then neutralizing the formed DDPA with a metal compound. It may be prepared according to known techniques. For example, dithiophosphoric acid can be prepared by reacting a mixture of primary and secondary alcohols. Alternatively, multiple dithiophosphoric acids may be prepared in which one hydrocarbyl group is completely secondary in nature and the other hydrocarbyl group is completely primary in nature. To prepare metal salts, any basic or neutral metal compound can be used, but oxides, hydroxides and carbonates are most commonly used. Conventional additives often contain excess metal due to the use of excess basic metal compounds in the neutral reaction.

Zinc dihydrocarbyl dithiophosphate (ZDDP) is an oil soluble salt of dihydrocarbyl dithiophosphoric acid and can be represented by the formula:

[Wherein R and R 'are the same or different hydrocarbyl radicals having 1 to 18 carbon atoms, for example 2 to 12, and radicals such as alkyl, alkenyl, aryl, arylalkyl, alkaryl and cycloaliphatic radicals has exist]. R and R 'groups may be alkyl groups having 2 to 8 carbon atoms. Thus, the radicals are for example ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, amyl, n-hexyl, i-hexyl, n-octyl, decyl, dodecyl, octadecyl , 2-ethylhexyl, phenyl, butylphenyl, cyclohexyl, methylcyclopentyl, propenyl, butenyl. To obtain oil solubility, the total carbon number of dithiophosphoric acid (ie, R and R ') will generally be about 5 or more. Zinc dihydrocarbyl dithiophosphate may thus comprise zinc dialkyl dithiophosphate.

Other suitable components that can be used as phosphorus-based antiwear agents include, but are not limited to, any suitable organophosphorus compound such as phosphate, thiophosphate, di-thiophosphate, phosphite and salts and phosphonates thereof. . Suitable examples are tricresyl phosphate (TCP), di-alkyl phosphites (eg dibutyl hydrogen phosphite) and amyl acid phosphate.

Another suitable component is a complete reaction product from the reaction between a polyamine and a hydrocarbyl substituted succinic acylating agent combined with a phosphorus source such as phosphorylated succinimides such as inorganic or organic phosphoric acid or esters. It may also include compounds in which the product may have amide, amidine and / or salt linkages in addition to imide linkages of the type resulting from the reaction of primary amino groups with anhydride moieties.

Phosphorus-based antiwear agents may be present in the lubricating composition in an amount sufficient to provide about 200 to about 2000 ppm phosphorus. As a further example, the phosphorus-based antiwear agent may be present in the lubricating composition in an amount sufficient to provide about 500 to about 800 ppm phosphorus.

Phosphorus-based anti-wear agents can range from about 1.6 to about 3.0 (ppm / ppm) of alkali and / or alkaline earth metal content (ppm) to the total amount of phosphorus in the lubricating composition based on the total amount of alkali and / or alkaline earth metal in the lubricating composition. It may be present in the lubricating composition in an amount sufficient to provide a percentage of phosphorus content (ppm) based on the basis.

Friction modifier

Embodiments of the present disclosure may include one or more friction modifiers. Suitable friction modifiers may include metal-containing and metal-free friction modifiers and include, without limitation, imidazolines, amides, amines, succinimides, alkoxylated amines, alkoxylated ether amines, amine oxides, amidoamines, nitriles, Betaines, quaternary amines, imines, amine salts, amino guanadines, alkanolamides, phosphonates, metal-containing compounds, glycerol esters, and the like.

Suitable friction modifiers may contain hydrocarbyl groups selected from straight chain, branched chain or aromatic hydrocarbyl groups or mixtures thereof and may be saturated or unsaturated. Hydrocarbyl groups may consist of carbon and hydrogen or hetero atoms such as sulfur or oxygen. Hydrocarbyl groups may have a carbon atom in the range of about 12 to about 25, and may be saturated or unsaturated.

The amine friction modifier may comprise an amide of a polyamine. The compound may be linear and have saturated or unsaturated hydrocarbyl groups or mixtures thereof, having about 12 to about 25 carbon atoms.

Further examples of suitable friction modifiers include alkoxylated amines and alkoxylated ether amines. The compound may have a linear, saturated, unsaturated hydrocarbyl group or mixtures thereof. It may contain about 12 to about 25 carbon atoms. Examples include ethoxylated amines and ethoxylated ether amines.

Amines and amides can be used on their own or in the form of adducts or reaction products with boron compounds such as boron oxide, boron halides, metaborate, boric acid or mono-, di- or tri-alkyl borates. Other suitable friction modifiers are described in US 6,300,291, which is incorporated herein by reference.

Other suitable friction modifiers may include organic, ashless (metal-free), nitrogen-free organic friction modifiers. The friction modifier may include esters formed by reacting carboxylic acids and anhydrides with alkanols. Other useful friction modifiers generally include polar end groups (eg, carboxyl or hydroxyl) covalently bonded to the lipophilic hydrocarbon chain. Esters of carboxylic acids and anhydrides and alkanols are described in U.S. Pat. 4,702,850. Another example of an organic ashless nitrogen-free friction modifier is generally known as glycerol monooleate (GMO) which may contain mono- and diesters of oleic acid. Other suitable friction modifiers are described in US 6,723,685, incorporated herein by reference. The ashless friction modifier may be present in the lubricating composition in an amount ranging from about 0.1 to about 0.4 weight percent based on the total weight of the lubricating composition.

Suitable friction modifiers may also include one or more molybdenum compounds. Molybdenum compounds include molybdenum dithiocarbamate (MoDTC), molybdenum dithiophosphate, molybdenum dithiophosphinate, molybdenum xanthate, molybdenum thioxate, molybdenum sulfide , Trinuclear organo-molybdenum compounds, molybdenum / amine complexes and mixtures thereof.

In addition, the molybdenum compound may be an acidic molybdenum compound. Included are molybdate, ammonium molybdate, sodium molybdate, potassium molybdate and other alkali metal molybdates and other molybdenum salts, such as sodium hydrogen molybdate, MoOCl ₄ , MoO ₂ Br ₂ , Mo ₂ O ₃ Cl ₆ , molybdenum trioxide or pseudo acidic molybdenum compound. Alternatively, see, eg, US Pat. No. 4,263,152; 4,285,822; 4,283,295; 4,272,387; 4,265,773; 4,261,843; 4,259,195 and 4,259,194; And molybdenum / sulfur complexes of the basic nitrogen compounds described in WO 94/06897.

Suitable molybdenum dithiocarbamates can be represented by the formula:

[Wherein, R ₁ , R ₂ , R ₃ , and R ₄ are each independently a hydrogen atom, a C ₁ to C ₂₀ alkyl group, C ₆ to C ₂₀ A cycloalkyl, aryl, alkylaryl or aralkyl group or C ₃ to C ₂₀ hydrocarbyl group (containing ester, ether, alcohol or carboxyl group); X ₁ , X ₂ , Y ₁ , and Y ₂ each independently represent a sulfur or oxygen atom.

Examples of suitable groups for each of R ₁ , R ₂ , R ₃ , and R ₄ are 2-ethylhexyl, nonylphenyl, methyl, ethyl, n-propyl, iso-propyl, n-butyl, t-butyl, n-hexyl , n-octyl, nonyl, decyl, dodecyl, tridecyl, lauryl, oleyl, linoleyl, cyclohexyl and phenylmethyl. R ₁ to R ₄ may each be a C ₆ to C ₁₈ alkyl group. X ₁ and X ₂ may be the same, and Y ₁ and Y ₂ May be the same. X ₁ and X ₂ may both contain sulfur atoms and Y ₁ and Y ₂ may both contain oxygen atoms.

Further examples of molybdenum dithiocarbamate include C ₆ -C ₁₈ dialkyl or diaryldithiocarbamate or alkyl-aryldithiocarbamate such as dibutyl-, diamyl-di- (2-ethyl Hexyl)-, dilauryl-, dioleyl-, and dicyclohexyl-dithiocarbamate.

Another class of suitable organo-molybdenum compounds is a trinuclear molybdenum compound, such as the formula Mo ₃ S _k L _n Q _z , wherein L is a suitable number to provide a compound that is soluble or dispersible in oil. N represents independently selected ligands having organo groups with carbon atoms, n is from 1 to 4, k can vary from 4 to 7, and Q is a neutral electron donating compound such as water, amines, alcohols, phosphines and ethers And z is in the range of 0 to 5 and comprises nonstoichiometric values) and mixtures thereof. At least 21 total carbon atoms such as at least 25, at least 30, or at least 35 carbon atoms may be present in the organic groups of all ligands. Further suitable molybdenum compounds are described in US 6,723,685, which is incorporated herein by reference.

The molybdenum compound may be present in the fully formulated engine lubricant in an amount to provide about 5 ppm to 800 ppm molybdenum. As a further example, the molybdenum compound may be present in an amount to provide about 30 to 100 ppm molybdenum.

Titanium compounds may also be included in the lubricating composition as friction modifiers. Titanium compounds are generally described in US Pat. No. 7,615,519; 7,615,520; 7,709,423; 7,776,800; 7,767,632; 7,772,167; 7,879,774; 7,897,548; 8,008,237; Reaction products of titanium alkoxides such as titanium isopropoxide and carboxylic acids having 6 to 25 carbon atoms as described in 8,048,834, the disclosure of which is incorporated herein by reference.

Antifoam

In some embodiments, the foam inhibitor can form another component suitable for use in the composition. Foam inhibitors can be selected from silicones, polyacrylates, and the like. The amount of antifoam in the engine lubricating formulations described herein can range from about 0.001% to about 0.1% by weight based on the total weight of the formulation. As a further example, the antifoam may be present in an amount from about 0.004% to about 0.008% by weight.

Antioxidant inhibitor components

Oxidation inhibitors or antioxidants reduce the tendency to deteriorate during operation of the base stock, which can be demonstrated by degradation products such as sludge and varnish-like deposits deposited on the metal surface and by increasing the viscosity of the final lubricant. Let's do it. The oxidation inhibitors are metals of hindered phenols, sulfided hindered phenols, alkaline earth metal salts of alkylphenolthioesters having C ₅ to C ₁₂ alkyl side chains, sulfided alkylphenols, sulfided or unsulfated alkylphenols, as described in US Pat. No. 4,867,890. Salts such as calcium nonylphenol sulfides, ashless oil-soluble phenates and sulfide phenates, phosphorus or sulfide hydrocarbons, phosphorus esters, metal thiocarbamates and oil-soluble copper compounds.

Additional antioxidants that may be used include sterically hindered phenols and esters thereof, diarylamines, alkylated phenothiazines, sulfide compounds and ashless dialkyldithiocarbamates. Non-limiting examples of sterically hindered phenols include, without limitation, 4-ethyl-2,6-di-tert-butylphenol, 4-propyl-2,6-di-tert-butyl, as described in US Publication No. 2004/0266630. Phenol, 4-butyl-2,6-di-tert-butylphenol, 4-pentyl-2,6-di-tert-butylphenol, 4-hexyl-2,6-di-tert-butylphenol, 4-heptyl -2,6-di-tert-butylphenol, 4- (2-ethylhexyl) -2,6-di-tert-butylphenol, 4-octyl-2,6-di-tert-butylphenol, 4-nonyl -2,6-di-tert-butylphenol, 4-decyl-2,6-di-tert-butylphenol, 4-undecyl-2,6-di-tert-butylphenol, 4-dodecyl-2, 6-di-tertiary butylphenol, methylene crosslinked hindered phenols such as, without limitation, 4,4-methylenebis (6-tert-butyl-o-cresol), 4,4-methylenebis (2-tert-amyl-o -Cresol), 2,2-methylenebis (4-methyl-6-tert-butylphenol, 4,4-methylene-bis (2,6-di-tert-butylphenol) and mixtures thereof. The hindered phenolic compounds do not affect the intake valve deposits and the antioxidant properties of the lubricant It can be used in addition to the aromatic compounds described herein for the purpose of improving In other words, the antioxidant is used in an amount that provides an antioxidant effect without reducing the amount of deposits on the intake valves of the SIDI engine.

Diarylamine antioxidants include, without limitation, diarylamines of the formula:

Wherein R and R "each independently represent a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. Examples of substituents for the aryl group include aliphatic hydrocarbon groups such as alkyl having 1 to 30 carbon atoms, hydroxy groups, halogen radicals, and carbon atoms. Acidic or ester groups or nitro groups.

The aryl group is particularly preferably substituted or unsubstituted phenyl or naphthyl, in which one or all of the aryl groups are substituted with one or more alkyl groups having 4 to 30, preferably 4 to 18, most preferably 4 to 9 carbon atoms. . Preference is given to, for example, mono-alkylated diphenylamines, di-alkylated diphenylamines or mixtures of mono- and di-alkylated diphenylamines with one or all aryl groups substituted.

Diarylamines may be structures containing more than one nitrogen atom in a molecule. Thus, diarylamines represent two or more nitrogen atoms with two or more aryl groups having one or more nitrogen atoms attached thereto, as in the case of various diamines having, for example, two aryl and secondary nitrogen atoms on one of the nitrogen atoms. It may contain.

Examples of diarylamines that can be used include, without limitation: diphenylamine; Various alkylated diphenylamines; 3-hydroxydiphenylamine; N-phenyl-1,2-phenylenediamine; N-phenyl-1,4-phenylenediamine; Monobutyldiphenyl-amine; Dibutyldiphenylamine; Monooctyldiphenylamine; Dioctyldiphenylamine; Monononyldiphenylamine; Dinonyldiphenylamine; Monotetradecyldiphenylamine; Ditetradecyldiphenylamine, phenyl-alpha-naphthylamine; Monooctyl phenyl-alpha-naphthylamine; Phenyl-beta-naphthylamine; Monoheptyldiphenylamine; Diheptyl-diphenylamine; p-oriented styrenated diphenylamine; Mixed butyloctyldi-phenylamine; And mixed octylstyryldiphenylamine.

Sulfur containing antioxidants include, but are not limited to, sulfide olefins characterized by the type of olefins used in their preparation and the final sulfur content of the antioxidant. High molecular weight olefins, ie olefins having an average molecular weight of 168 to 351 g / mole, are preferred. Examples of olefins that can be used include alpha-olefins, isomerized alpha-olefins, branched olefins, cyclic olefins and combinations thereof.

Alpha-olefins include, but are not limited to any C ₄ to C ₂₅ alpha-olefins. The alpha-olefins may be isomerized prior to or during the sulfidation reaction. Structural and / or conformational isomers of alpha olefins containing internal double bonds and / or branches may also be used. Isobutylene, for example, is a branched olefin counterpart of alpha-olefin 1-butene.

Sulfur sources that can be used for the sulfidation of olefins include: elemental sulfur, sulfur monochloride, sulfur dichloride, sodium sulfide, sodium polysulfide and mixtures thereof added together or at different stages of the sulfiding process.

Due to their unsaturation, unsaturated oils can also be sulfided and used as antioxidants. Examples of oils or fats that can be used are corn oil, canola oil, cotton seed oil, grape seed oil, olive oil, palm oil, peanut oil, coconut oil, rapeseed oil, safflower oil, sesame seed oil, soybean oil, sunflower seed oil , Uji and combinations thereof.

The amount of sulfided olefin or sulfided fatty oil delivered to the final lubricant is based on the sulfur content of the sulfided olefin or fatty oil and the desired level of sulfur to be delivered to the final lubricant. For example, sulfurized fatty oils or olefins containing 20% by weight sulfur will deliver 2000 ppm of sulfur to the final lubricant when added to the final lubricant at a 1.0% by weight treatment level. When added to the final lubricant at a 1.0 wt% treatment level, sulfided fatty oils or olefins containing 10 wt% sulfur will deliver 1000 ppm of sulfur to the final lubricant. Sulfurized olefins or sulfided fatty oils preferably deliver between 200 ppm and 2000 ppm sulfur to the final lubricant.

In general terms, suitable engine lubricants may include additive components in the ranges listed in the table below.

Additional optional additives that may be included in the lubricating compositions described herein include, but are not limited to, rust inhibitors, emulsifiers, deemulsifiers and oil soluble titanium-containing additives.

The additives used in the formulation of the compositions described herein can be formulated into the base oil individually or in various sub-combinations. However, it may be suitable to combine all the components simultaneously using additive concentrates (ie additives + diluents such as hydrocarbon solvents). The use of additive concentrates can take advantage of the mutual compatibility imparted by the combination of components when in the form of additive concentrates. In addition, the use of concentrates can reduce blending time and reduce the likelihood of blending mistakes.

The present disclosure particularly provides novel lubricating oil formulations formulated for use as private engine lubricants in SIDI engines. In order to demonstrate the benefits and advantages of the lubricating composition according to the present disclosure, the following non-limiting examples are provided.

Example

In this evaluation, two identically equipped 2008 Pontiac Solstice test vehicles using SIDI fuel management were used. Both cars had previously used conventional fully formulated engine oils in their crankcases, which are SAE 5W-30 motor oils that meet the ILSAC GF-4 specification. All cars produced significant intake valve deposits that would cause a loss of engine efficiency and must be mechanically removed from the maintenance process before engine damage. If left to accumulate, the deposit will cause the final seizure of the intake valve of the valve guide.

Before starting the test, the valves and ports of both vehicles were disassembled, cleaned and reassembled. For test car 1, the baseline fully formulated engine oil recommended by the car manufacturer was used. For test vehicle 2, SAE 5W-30 test oil was used formulated to meet ILSAC GF-4 and GF-5 requirements and containing the aromatic compounds described herein.

Both vehicles were driven with a Mileage Accumulation Dynamometer (MAD) according to the in-house “four wheel” drive cycle used to test fuel effects on combustion chamber deposits. Since the fuel does not interact with the intake valve, it was considered not a test variable. The evaluation concluded at 35,184 miles when the test car 1 produced enough deposits to cause a loss of engine efficiency due to limited air flow in and around the intake valve. Test car 2 was still operating normally at 80912 miles.

1 is a photograph of one of the representative intake valve ports and valve stems of a test vehicle 1 after 35,184 miles driven with a conventional engine oil composition. Due to previous valve clogging experience, the experimenters found that there was sufficient accumulation to indicate impending valve clogging. FIG. 2 is a close-up photograph of deposits on the valve stem of FIG. 1. FIG.

From previous experience, it is known that the oily deposits shown in FIGS. 1 and 2 are derived from recycled crankcase gas containing vaporized engine oil. Since the SIDI engine does not use port fuel injection, there is no fuel for cleaning oily deposits from the valve stem and port that will occur in the port fueled engine.

3 is a photograph of one of the representative intake valve ports and valve stems of car 2 after the car has been driven for 80912 miles. 4 is a close-up photograph of the valve stem of FIG. 3.

As shown in Figures 3 and 4, the appearance of ports and valves from motor vehicles using the aromatic compounds described herein were quite different. The deposits shown by FIGS. 3 and 4 showed no traces of oily deposits. In contrast to FIGS. 1 and 2, the deposits shown in FIGS. 3 and 4 have an ash-like appearance. The ash is believed to be derived from metallic compounds used in oil compositions, such as zinc dithio-phosphate anti-wear additives, and metallic compounds used in calcium sulfonate detergents. The oil fraction was evaporated, leaving ash component. Deposits such as ash were well torn and the valves moved up and down in the guides and ports of the engine, making them easy to peel off from the valves and valve stems. The aromatic compound additives described herein are believed to stabilize the oily deposits long enough to allow time for natural vaporization of the oil component in the deposits, leaving only ash residues on the valve stems and ports. In contrast, the oily deposits shown in FIGS. 1 and 2 formed larger and harder deposits, and this experience taught to cause valve scissor.

In many places throughout this specification, reference has been made to many US patents. All of the above mentioned documents are incorporated by reference in their entirety in this disclosure as if fully set forth herein.

Other embodiments of the present disclosure will be apparent to those skilled in the art in connection with the practice of the specification and the embodiments disclosed herein. As used throughout this specification and claims, the singular number may refer to one or more than one. Unless otherwise indicated, all numbers, properties such as molecular weight, percentages, ratios, reaction conditions, etc., expressing quantities of ingredients used in the specification and claims are to be understood as being modified in all cases by the term "about". Thus, unless indicated to the contrary, the numerical parameters set forth in this specification and claims are approximations that may be modified in accordance with the desired properties sought to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the principle of equivalence to the scope of the claims, each numerical parameter should at least be construed by considering at least reported significant digits and applying ordinary rounding techniques. . Notwithstanding that the numerical ranges and parameters set forth in the broad scope of the invention are approximations, the numerical values set forth in the specific examples are represented as precisely as possible. However, any numerical value includes certain errors which inevitably arise from the standard deviation originally found in its representative test measurement. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

This embodiment may allow for practically conceivable differences. Accordingly, embodiments are not intended to be limited to the particular examples presented herein above. More precisely, the embodiments are within the spirit and scope of the appended claims, including their equivalents as legal matters.

The patentee does not intend any disclosed embodiment to be disclosed, and to the extent that any disclosed variation or alternative may not be literally within the scope of the claims, it is considered part of this application on an equivalent basis.

Claims (16)

A lubricating additive effective in reducing intake valve deposits in a direct injection spark ignition (SIDI) engine comprising an aromatic compound having a boiling point of from about 190 to about 270 ° C. under standard atmospheric conditions, the aromatic compound comprising A lubricating additive effective to reduce intake valve deposits in SIDI engines when used in amounts ranging from about 0.1 to about 5.0 weight percent based on total weight. The compound of claim 1, wherein the aromatic compound is 2,6-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-6-methylphenol, 2-tert- A lubricating additive selected from the group consisting of butylphenol, 4-tert-butylphenol, o-cresol, m-cresol, p-cresol and mixtures of two or more thereof. The lubricating additive of claim 1 wherein the aromatic compound comprises 2,6-di-tert-butylphenol. A lubricating composition comprising about 0.5 to about 2.0 weight percent of a lubricating additive according to claim 1. A lubrication promoting additive for addition to a SIDI engine crankcase comprising the lubricating additive according to claim 1. Providing the engine crankcase with a lubricating composition comprising an aromatic compound having an boiling point of from about 190 to about 270 ° C. under a predetermined amount of standard atmospheric conditions sufficient for the amount of aromatics to reduce the intake valve deposits; Operating the engine for a period of time sufficient to vaporize at least a portion of the aromatic compound to contact the intake valve of the engine. The compound of claim 1, wherein the aromatic compound is 2,6-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-6-methylphenol, 2-tert- Butylphenol, 4-tert-butylphenol, o-cresol, m-cresol, p-cresol and mixtures of two or more thereof. 8. The method of claim 7, wherein the aromatic compound comprises 2,6-di-tert-butylphenol. The method of claim 6, wherein the amount of aromatic compound in the lubricating composition ranges from about 0.1 to about 5.0 weight percent based on the total weight of the lubricating composition. The method of claim 6, wherein the amount of aromatic compound in the lubricating composition ranges from about 0.5 to about 2.0 weight percent based on the total weight of the lubricating composition. Crankcase for direct injection spark ignition (SIDI) engines comprising aromatics having a boiling point of about 190 to about 270 ° C. under a predetermined amount of standard atmospheric conditions sufficient to reduce the intake valve deposits of the SIDI engine. Lubricating composition. 12. The compound of claim 11, wherein the aromatic compound is 2,6-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-6-methylphenol, 2-tert- Crankcase lubricating composition selected from the group consisting of butylphenol, 4-tert-butylphenol, o-cresol, m-cresol, p-cresol and mixtures of two or more thereof. The crankcase lubricating composition of claim 11, wherein the amount of aromatic compound in the lubricating composition ranges from about 0.1 to about 5.0 weight percent based on the total weight of the lubricating composition. The crankcase lubricating composition of claim 11, wherein the amount of aromatic compound in the lubricating composition ranges from about 0.5 to about 2.0 weight percent based on the total weight of the lubricating composition. 12. The composition of claim 11 comprising detergents, dispersants, friction modifiers, antioxidants, corrosion inhibitors, viscosity index enhancers, emulsifiers, deemulsifiers, corrosion inhibitors, antiwear agents, metal dihydrocarbyl dithiophosphates, ashless amine phosphate salts, A crankcase lubricating composition further comprising at least one member of the group selected from antifoam and pour point depressant. The crankcase lubricating composition of claim 11, further comprising an oil soluble titanium-containing additive.

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